Journal of the Korean Society for Aeronautical & Space Sciences (한국항공우주학회지)

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
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Computation of Wake Vortex Behavior Behind Airplanes in Close Formation Flight Using a Fourier-Spectral Method

푸리에-스펙트럴 법을 사용한 근접 편대비행 항공기의 와 거동 계산

  • Ji, Seunghwan (Department of Aeronautical and Mechanical Design Engineering, Korea National University of Transportation) ;
  • Han, Cheolheui (Department of Aeronautical and Mechanical Design Engineering, Korea National University of Transportation)
  • Received : 2019.08.01
  • Accepted : 2019.11.27
  • Published : 2020.01.01
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Abstract

Behaviors of wake vortices generated by an aircraft affect the performance and flight stability of flying aircraft in formation flight. In the present study, the trajectories of the wake vortices behind airplanes in close formation flight were computed using a Fourier spectral method. The behavior of wake vortices showed complex patterns depending on the initial circulation and the relative positions between the vortices. In the initial stage, the wake vortex movement was affected by the nascent vortex. When the vortex becomes closer to the other vortex, then a new trajectory is formed. When the viscous effect becomes dominant, the core radius increases. Thus, a new vortex moving near the existing vortex can have strong interaction with each other, resulting in the complicated behavior of wake vortices. In the future, the ground effect on the behavior of the wake vortices during take-off and landing will be studied.

항공기에서 발생한 후류의 거동은 항공기의 성능과 비행안정성에 큰 영향을 미친다. 본 연구에서는 푸리에-스펙트럴법을 사용하여 근접 편대비행을 하고 있는 항공기 날개 후류 거동에 관하여 연구하였다. 초기와의 순환강도, 상대위치 등에 따라 와들의 거동이 복잡한 양상으로 나타났다. 와의 순환강도 값이 큰 경우 와들의 이동이 크게 나타났다. 초기에는 가까이 위치한 와의 영향을 받아 이동하지만 이동하는 과정에서 다른 와와 가깝게 되면 새로운 경로를 형성하였다. 점성이 클수록 와의 반경이 증가하여 와 반경 근처로 새롭게 진입하는 와와 상호작용이 강해진다. 향후 항공기가 이착륙 시에 발생하는 지면 효과를 고려한 후류 거동 해석 연구를 수행하고자 한다.

Keywords

References

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